The largest high-speed catamaran in the Mediterranean has been launched
Virtu Ferries’ 110-m, wave piercing catamaran Saint John Paul II was built by shipbuilder Incat in Hobart, Australia. With a service speed up to 38 knots it will complete the crossing from Malta to Sicily, berth-to-berth, in around 90 minutes.
For Virtu Ferries, this new vessel provides a significant increase in capacity, the 490 truck lane metres offering 43% more truck capacity, with 15% more passenger capacity and 7% more car capacity than its previous craft.
Incat Tasmania chairman Robert Clifford said “Virtu Ferries were looking for increased reliability, sea keeping, passenger comfort, capacity and economy with less operational downtime.”
Highlighting one of the most important aspects in the construction, he said “We make it as lightweight as possible. We do this by trying to buy the lightest components that we can.”
The contract is an important one for Incat. “It is a very interesting contract for us as we have known Virtu Ferries for many years but have not worked with them before.”
Saint John Paul II is the first in its class and is replacing a ship built by Austal.
The design was modelled by Revolution Design and Seaspeed Marine Consulting and extensively tank-tested and optimised at QinetiQ, the tank and aerospace testing facility in the UK which was purpose built for use by the British Navy and UK Ministry of Defence.
Mr Clifford explained that the shipyard designed the vessel, but incorporated Seaspeed Consulting’s ideas into the design. He gave an example: “We designed with [Seaspeed's] output a higher tunnel clearance, making it more efficient compared to our normal fleet.”
Credit: Walter Pless
The design consists of two slender, aluminium hulls connected by a bridging section with a centre bow structure at the forward end. Each hull is divided into 10 vented, watertight compartments divided by transverse bulkheads. Two compartments in each hull are prepared as fuel tanks with additional strengthening on each of the end bulkheads and intermediate tank tops.
The main engines are four mounted MTU58000M71L models, combined with four Wartsila LJX 1500SR waterjets configured for steering and reverse. Transmission consists of four ZF60000 gearboxes, approved by the engine manufacturer, with a reduction ratio suited for optimum jet shaft speed. There are five hydraulic power packs, one forward, four aft.
Mr Clifford said “We always use waterjets for efficiency – propellers cease to be efficient at 30 knots so any vessel running at 35-40 knots is almost always fitted with waterjets – the question is which ones.”
He observed that there are three similar types for this size of catamaran. “We did some calculations and concluded that Wärtsilä was best for this vessel.”
Speaking about the engine choice, he said “MTU engines are very energy efficient. They were the customer’s choice.”
On the electrical side, there are four x 300ekW MTU8V2000M51A generators. The generators are arranged for automatic start up and paralleling. The automation will consider one generator maintained as a standby set.
A Naiad active ride control system is fitted to maximise passenger comfort. This system combines active trim tabs aft and two hull mounted T-foils. Mr Clifford said “These T-foils are larger than those we would normally fit. The client was particularly interested in making the boat very comfortable in rough sea [which is what these do].” Their size meant there was no room for them to be fitted on the dock and so they had to be fitted once the boat was launched into water.
The air conditioning consists of a water cooled air conditioning plant and reverse cycle heat pump units capable of maintaining between 20-22°C and 50% RH with a full passenger load and ambient temperature of between 12°C and 32°C and 80 % RH. Mr Clifford commented that the system was very energy efficient but singled out a challenge. “It was more complex to fit as it was a lot heavier [than Incat would normally use in a high-speed craft].”
The evacuation system consists of four marine evacuation stations (MES), two port and two starboard. Each MES is capable of serving up to 300 people. Eleven 100-person liferafts are fitted.
There are also two SOLAS inflatable dinghies with 25 hp motors and approved launch/recovery method.
The ferry has been built under the DNV-GL classification society rules and complies with IMO High Speed Craft HSC 2000, the Malta flag statutory requirements and Italian port state requirements.
Designer: Revolution Design
Builder: Incat Tasmania
Class society: DNV GL
Length overall: 110.6 m
Length waterline: 101.9 m
Beam moulded: 28.2 m
Beam of hulls: 5.4 m
Draft: 4.277 (+/-0.2m)
Speed: 37.5 knots at 85% MCR, 600 dwt
Deadweight: 1,000 tonnes.
Passenger Capacity: 924 people (including crew)
Passenger decks: Located on two levels, consisting of:
- Tourist class passenger seating areas (Tier 2)
- Truck drivers lounge (Tier 2)
- Business class passenger seating area (Tier 3)
- 2 x VIP lounges (Tier 3)
- Bars (x3), gift shop, gaming lounge
Crew accommodation: Sleeping cabins for 24 crew members
Vehicle capacity: 490 truck lane metres at 3.5m wide and 4.6m clear height or up to 167 cars at 4.5 m length x 2.4 m wide
Axle loads: 12 tonnes (single axle single wheel) or 15 tonnes (single axle dual wheel)
Tankage MGO fuel oil (storage tanks): 492,000 litres
Fuel oil (header tanks): 2 x 5,000 litres
Fuel oil (separator tanks): 2 x 5,000 litres
Fresh water: 2 x 6,500 litres
Sewage: 6,500 litres
Lube oil: 2 x 1,100 litres
Oily bilge water: 2,000 litres
Aft hydraulic oil: 2 x 500 litres
Fwd hydraulic oil: 500 litres